In many grinding processes, eg. in the manufacture of cams and crankshafts, it is usual for the initial major grinding operation to be performed by rough grinding using a coarse grade grinding wheel and for the final grinding operation to be performed by a fine grade grinding wheel. If the whole grinding process is to be performed on a single machine then two main options are available: either the machine has a single spindle which means that at each successive grinding operation the coarse wheel must be replaced by the fine wheel and vice versa, which significantly increases the total time required to grind a component; or alternatively the machine must be designed to have two spindles carrying respectively coarse and fine grinding wheels, which considerably increases the complexity and hence cost of the grinding machine.
It is an object of the present invention to produce an improved method of and apparatus for grinding, in which the coarse rough and final grinding operations are performed on a single spindle of a machine tool.